The party has turned against its historic objection to nuclear power by 230 votes to 183 to accept “nuclear power stations could play a limited role in electricity supply”.
This support comes provided concerns about safety, cost and disposal of nuclear waste are “adequately addressed with”.
Speaking at the conference, energy secretary Ed Davey, who led the party’s anti-nuclear stance in 2006, said he had changed his mind because of the “real and massive danger to our planet” from climate change.
He added: “Not keeping a genuine low carbon source of electricity as an option looks reckless”, saying that the amount of low carbon electricity needed in the future will be “vast” and that he was no longer sure this could be met from renewables and energy efficiency measures alone.
Liberal Democrat delegates also showed strong support for fracking provided tight environmental regulations are put in place.
The amendment which party members supported also allowed communities to benefit from both shale gas exploration and production, including giving them a right to buy into shale gas projects.
Alongside this, the policy motion would also establish a low carbon transition fund, which would take half the shale gas exploration and production income to fund strong fracking regulations, low carbon innovations to tackle fuel poverty and to encourage the commercialisation of carbon capture and storage technology.